<title>表达式括号匹配</title><link href="http://hzoi.com/tomorrow.css" rel="stylesheet"><div class="ui existing segment"><pre><code><span class="pl-cp">#include</span><span class="pl-cpf">&lt;cstdio&gt;</span><span class="pl-cp"></span>
<span class="pl-kt">int</span> <span class="pl-nf">main</span><span class="pl-p">(){</span>
	<span class="pl-n">freopen</span><span class="pl-p">(</span><span class="pl-s">&quot;bracket.in&quot;</span><span class="pl-p">,</span><span class="pl-s">&quot;r&quot;</span><span class="pl-p">,</span><span class="pl-n">stdin</span><span class="pl-p">);</span>
	<span class="pl-n">freopen</span><span class="pl-p">(</span><span class="pl-s">&quot;bracket.out&quot;</span><span class="pl-p">,</span><span class="pl-s">&quot;w&quot;</span><span class="pl-p">,</span><span class="pl-n">stdout</span><span class="pl-p">);</span>
	<span class="pl-kt">char</span> <span class="pl-n">s</span><span class="pl-p">[</span><span class="pl-mi">300</span><span class="pl-p">]</span><span class="pl-o">=</span><span class="pl-p">{</span><span class="pl-mi">0</span><span class="pl-p">};</span>
	<span class="pl-n">scanf</span><span class="pl-p">(</span><span class="pl-s">&quot;%s&quot;</span><span class="pl-p">,</span><span class="pl-n">s</span><span class="pl-p">);</span>
	<span class="pl-kt">int</span> <span class="pl-n">top</span><span class="pl-o">=</span><span class="pl-mi">0</span><span class="pl-p">;</span>
	<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span><span class="pl-o">=</span><span class="pl-mi">0</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">&lt;</span><span class="pl-mi">300</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">++</span><span class="pl-p">){</span>
		<span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-o">!</span><span class="pl-n">s</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">]</span> <span class="pl-o">||</span> <span class="pl-n">s</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">]</span><span class="pl-o">==</span><span class="pl-sc">&#39;@&#39;</span><span class="pl-p">)</span><span class="pl-k">break</span><span class="pl-p">;</span>
		<span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">s</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">]</span><span class="pl-o">==</span><span class="pl-sc">&#39;(&#39;</span><span class="pl-p">)</span><span class="pl-n">top</span><span class="pl-o">++</span><span class="pl-p">;</span>
		<span class="pl-k">else</span> <span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">s</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">]</span><span class="pl-o">==</span><span class="pl-sc">&#39;)&#39;</span><span class="pl-p">)</span><span class="pl-n">top</span><span class="pl-o">--</span><span class="pl-p">;</span>
	<span class="pl-p">}</span>
	<span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">top</span><span class="pl-o">==</span><span class="pl-mi">0</span><span class="pl-p">)</span><span class="pl-n">printf</span><span class="pl-p">(</span><span class="pl-s">&quot;YES&quot;</span><span class="pl-p">);</span>
	<span class="pl-k">else</span> <span class="pl-n">printf</span><span class="pl-p">(</span><span class="pl-s">&quot;NO&quot;</span><span class="pl-p">);</span>
	<span class="pl-k">return</span> <span class="pl-mi">0</span><span class="pl-p">;</span>
<span class="pl-p">}</span>
</cpde></pre></div>